Currently, for creating ambience in certain occasions, people often use imitation candle lamps to imitate actual candle flame effect. A conventional imitation candle lamp commonly utilizes a flame piece supported on the lamp head, an illuminator emitting light to the flame piece, and a drive device for driving the flame piece to swing, thereby obtaining faux flame effect. However, the flame piece is supported on the lamp head by a wire, and the flame piece may swing at small amplitude due to its swing is limited by the wire. Thus the imitation effect is stiff and not lifelike. Besides, when the flame piece is mounted on the lamp head by a wire, friction occurs with the wire. Each time the drive device drives the flame piece, the flame piece can only swing once or twice because of friction, and then the drive device is required. When power is frequently turned on, which will result in consuming a large amount of electric energy, and the battery life of the imitation flame lamp is short, and it is not environmentally friendly.